Thank you for posting your question on Just Answer! I will be happy to help you with this problem. Can you please give us some more information so I can better answer your questions.
-What exactly does it do when you plug it in or turn it on? (light blink, click noise, ect.)
-How old is the unit?
Please give me this information and I will be happy to assist you further.
Any power problems or storms lately?
There is a fuse, if you take the back off and follow the power cord to where it plugs in, right near that will be the AC fuse.
Do you have a meter to check it with?
Check the voltages between the main board and the power supply, do you have anything?
Right now we are looking for a 5V standby
What do you mean by existing ground?
Ok that should be good, any bad capacitors on that board?
Nothing looks burnt or overheated if that's what you mean, after that, your going over my pay grade. is it worth going any further, replace the power supply if i could even find one???
hmm...Ok how about this, can you get me a picture of the power supply? (if you can post a picture, please click the icon above where you are typing with the green tree on it. This will allow you to upload a picture)
Ok sounds good, sorry we did not have a great outcome.